Ignition switch for automobiles and the like



0a In.

Patrick H. Childress June 22, 1948. P. H. CHILDRESS IGNITION SWITCH FORAUTOMOBILES AND THE LIKE Filed Dec. 6, 1946 I Patented June 22, 1948IGNITION SWITCH FOR AUTOMOBILES AND THE LIKE Patrick H. Childress,Waynesboro, Va., asslgnor of ten per cent to Dennis W. May, Waynesbcro,Va.

Application December 6, 1946, Serial No. 714,509

3 Claims. (01. 200-42) My invention relates to improvements in ignitionswitches for automobiles and similar vehicles.

The invention is designed with the primary object in view of providing asimply constructed, inexpensive, key operated switch, for the ignitioncircuits of automobiles, so arranged that the key must be removed tobreak the circuit and stop themotor, whereby negligent leaving ofignition keys in automobiles, and stealing of automobiles as a result ofsuch practice will be rendered impossible.

Another object is to provide a switch of the character and for thepurpose above set forth which is tamperproof as regards operation toclose the switch, by an unauthorized person.

Still another object is to provide an ignition switch which by slightchange in the key structure, principally, may be modified within a widerange of variation so as to provide individual ignition switches for alarge number of automobiles operative only by individual keys for thedifferent automobiles.

Still another object is to provide an-ignition switch which will notreadily get out of order,

as from wear, is substantially foolproof, and easy to install on anymake of automobile.

Other and subordinate objects, also comprehended by my invention,together with the precise nature of my improvements, and the manifoldadvantages thereof, will be readily understood when the succeedingdescription and claims are read with reference to the drawingaccompanying and forming part of this specification.

In said drawing:

Figure l is a view in perspective illustrating my improved switchapplied.

Figure 2 is a view in front elevation drawn to a larger scale with thecap member removed and illustrating the position of the parts when theswitch is open.

Figure 3 is a view in vertical transverse section taken on the line 8-3of Figure 1 and drawn to a larger scale.

Figure 4 is a fragmentary view similar to Figure 2 with the key guideshown in transverse section.

Figure 5 is a fragmentary view in horizontal section taken on the line5-5 oi' Figure 2.

Figure 6 is a similar view with the key shoved home.

Figure 'l is a view in side elevation illustrating the swingaablecontact arm in detail.

Figure 8 is a fragmentary view of the swingable contact arm inperspective.

Figure 9 is a fragmentary view in side elevation of the pilot post andthe lower key operated portion of the swingable contact arm.

Figure 10 is a view in end elevation of a modified form of key.

Referring to the drawing by numerals, my improved ignition switch, inthe preferred embodiment shown, comprises a switch housing I which maybe of any suitable form for use on the instrument panel 2 of anautomobile, but, preferably, comprises, as shown, a cup-like circular,rear member 3 and a dlsklike front, cap member 4.

The housing i is preferably secured to the instrument panel 2 behind thesame by means of screws 2 which extend through said panel and throughpairs of complemental ears 3, 4 on said rear member 3 and said capmember 4, and which together with said screws secure said memberstogether. The bottom of the rear memher 3 forms the back 5 of thehousing i. The housing i may be formed of any suitable material,preferably a plastic, or a metal if desired.

A tubular conduit 6 of any suitable material, extends from the back 5 ofthe housing I, eccentrically thereof, through the dash board I of theautomobile with jam nuts 8, 9 threaded thereon upon both sides of saiddash board. The tube 6 may take various forms and be fixed in anydesired manner to the back 5 for instance by solder ill if the rearmembers 3 be metal. The housing I is thus fixed to the instrument panel2 and to the dash board I with conduit 6 extending rearwardly from theupper portion of said housing. The conduit 6 serves to house theappropriate ends of the circuit. wires II for connection to one side ofthe switch, and a wire ii for connection to the other side of saidswitch, said wires being extended through said conduit into the housing8 as best shown in Figures 2 and 3.

A bus bar It, of conductive material, is mounted in, the upper part ofthe housing I adjacent to the conduit 6 to extend parallel with the back5 and crosswise of said conduit with a depending fixed contact M ofright angled cross section thereon. The mounting for the bus bar l3comprises, preferably, a pair of posts on the back 5 of the housing iand suitably insulated therefrom, one of which is shown in full lines atH, in Figure 3, and to which the ends of the bus bars I3 are suitablyfixed with the ends of the circuit wires i I fixed thereto by solder,not shown.

A pilot post ii, for an ignition key presently described, extendsforwardly from the back of the housing i in the lower part thereof anddiametrically opposite the conduit 8.

An upright, swingable contact arm I8 is pivoted intermediate its ends,by a fixed stud i3", on the back of the housing adjacent the bottomthereof, to one side of the fixed contact H, with an intermediateportion ll of insulation material through which the stud :6 extends, alower key operated end portion i8 of case hardened I steel, and an upperconductive end portion i9.

The end portions i8, 13 are set into the intermediate portion l1 andsecured therein by pins i8, I9. The end portion is is formed with aterminal loop i9 secured by a screw 20 around a contact screw 2|threaded through said loop and adapted to engage the fixed contact l4 ina manner presently seen. The wire 12 is soldered as at i2 to the loop I9A leaf spring 22 has one end suitably fixed in a post 23 on the back 5of the housing I, by a nut 24, and its other end bearing against thelower end portion i8 of the swingable contact arm i6 and guided by anotch 25 in said end portion, so that said spring acts to swing said armit to move the upper end portion i9 thereof away from the fixed contact84, and the lower end portion l8 of said arm toward the pilot post i5 atone side of said post.

A ke guide 26 in the form of a mutilated cylinder of suitable materialsurrounds the pilot post l5 and is fixed to the back 5 of the housing 1in the bottom portion of said housing and opposite the lower end portionii! of the swingable contact armiii, in horizontal alignment with anentrance opening 21, for the key, provided in the cap member 4 of thesaid housing The key guide 26 is provided with a key shaped guideway 28therein around the pilot post i5 and in the front portion of the guide,and with a side notch 29 therein opposite the lower end portion 58 ofthe swingable contact arm i6, and which exposes the pilot post E5 tosaid portion of said arm i3. A washer H"- on the stud I6 is overlappedby the front end of the key guide whereby said contact arm i6 is securedin place and cannot be removed unless the key guide 23 is removed. Thekey guide 25 is held in place by screws, as at 26 passing through theback 5 of the housing 8.

An ignition key 30 is provided with a tubular shank 3| having a beveledleading end 32 and a longitudinal radial rib 33, and which fits in theguideway 28 and on the pilot post |5 to be shoved into said guideway 28along said pilot post. An entrance opening 30 for the key 30 is providedon the instrument panel 2.

Returning now to the pilot post l5 and the lower end portion l8 of theswingable contact arm I6, said lower portion i3 is formed with a sideboss 34 adapted to fit, under the urge of the leaf spring 22, into aside notch 35 in the pilot post i5, with a concave beveled edge notch 36therein adapted to face the beveled end 32 of the key shank 3!, whensaid key is first inserted, but to be countersunk in said notch 35 so asto prevent said beveled end 32 from being shoved past the boss 34. Asmall corner portion 31 of the boss 34 extends slightly out of the notch35, when said edge 36 is countersunk in the notch 35, to be engaged bythe beveled end 32 of the key shank 3| and be cammed by said end awayfrom the pilot post I5 until the beveled edge 36 is moved out of thenotch 35 sufliciently to be engaged by th beveled end 32 of the said keyshank for complete camming of the boss 34 away from the pilot post I! bysliding of the key shank 3| home on the pilot post ii. The bottom of thenotch 35 and the opposed face of the boss 34 are oblique to the axis ofthe pilot post i5, as shown in Figur 5, for a. purpose presently seen.

' Referring now to the operation of the described switch. Normally, theswingable contact arm I6 is swung by the spring 22, clockwise as viewedin Figure 4, with the contact screw 2| disengaged from the fixed contactl4', and boss 34 fitted in the notch 35 and engaged with the bottom ofsaid notch 33. The only part of the boss 34 exposed out of the notch 35is the corner 31 of said boss, as best shown in Figure 9. The switch isnow open, as will be clear. To close the switch, the key shank 3| isinserted through the entrance openings 21 and 20' and into the guideway28 and pushed rearwardly along the pilot I 5. As the beveled end 32 ofthe shank 3| strikes the corner 31 of the boss 34, said boss isinitially cammed outwardly of the notch 35 to swing the swingablecontact arm I6 counter clockwise, as Viewed in Figure 4. and its upperend portion is, with the screw 2| thereon, toward the fixed contact [4.As the corner 31 rides up the beveled end 32 of the key shank 3 saidbeveled end 32 engages the beveled edge 36 and the boss 34 is cammedaway from the pilot post iii to an extent such that the screw 2| isengaged with the fixed contact l4 and the switch thus closed. As will beclear, when the switch is thus closed, the key shank 3| is interposedbetween the pilot post if: and the boss 34 to maintain the swingablecontact arm IS in switch closing position. Thus the switch is held closeby the key 30 and cannot open until said key is withdrawn. By having theboss 34, all but the corner 31 thereof, interposed in the notch 35 ofthe pilot post i5 when the switch is open, the swingable contact arm i6cannot be operated to close the switch by a piece of wire or likeinstrument inserted through the key way 28, nor by similar means.Actually, the corner 31 of the boss 34 constitutes substantially a pinpoint pick up abutment for engagement by the beveled end 32 of the keyshank 3| so that it is practically impossible to engage said corner withany other device except the beveled end 32 of the key shank 3| and in amanner such that the swingable contact arm i6 may be operated inopposition to the spring 22. The slant ofthe bottom of the notch 35 andthe face of the boss 34, provides for beveling the face of the boss 34to facilitate camming of the boss 34 by the beveled end 32 of the keyshank 3| and for a flush fit of the face of said boss in the notch 35preventing insertion of a tool between said notch and said boss to prythe boss 34 out of the notch 35. By varying the size of the pilot postl5, guideway 28 and key shank 3|, a large number of switches may be madefor operation by individual keys only. This end may also be achieved byvarying the shape of the rib of the key shank. as shown at 38 in Figure10, with corresponding variation in shape of the guideway 28.

The foregoing will, it is believed, sufilce to impart a clearunderstanding of my invention, without further explanation.

Manifestly, the invention, as described, is susceptible of modificationwithout departing from the inventive concept, and right is hereinreserved to such modifications as fall within the scope of the appendedclaims.

What I claim is:

1. A switch for use in the ignition circuit of an automobile comprisinga housing having a back opening therein for the extensionoi circuitwires into the housing, said housing having a front key entrance openingin the same, a pilot post fixed in said housing in the axis of the keyentrance opening, a contact arm pivoted in said housing for swinging inrelatively opposite di-' rections with one end opposed to one side ofsaid post, and adapted to engage the same upon swinging of said arm inone direction, spring means in said housing for swinging said arm insaid one direction, a key having a tubular shank for insertion throughsaid entrance opening and sliding along said post to interpose the shankbetween said post and arm and thereby swing said arm in'the oppositedirection, coacting camming devices on said key shank and said armrespectively for swinging said arm as said shank is slid along saidpost, a fixed contact in said housing for engagement by said arm whensaid arm is swung in said opposite direction, means on said arm forconnecting one of said circuit wires thereto, and means in said housingfor connecting the other circuit wires to the fixed contact.

2. A switch oi the class described comprising a housing having a keyentrance opening therein, a fixed contact in the housing, a pivotedcontact arm in said housing swingable in opposite directions to engageand disengage the ilxed contact, respectively. a key piloting post insaid housing axially aligned with said opening and having a side notchtherein. a boss on one end of said arm adapted to be entered in saidnotch when said .arm is swung to disengage said fixed contact.

spring means for swinging said arm to disengage the same from the fixedcontact. a key having a tubular shank for insertion through said openingand sliding along said post forwardly, a beveled end on said shank forcamming engagement with said boss to cam the same out of the notch andswing said arm into engagement with the fixed contact when said shank isslid forwardly, said boss having a corner exposed out of said notch forcamming engagement by said beveled end to initially cam the bossoutwardly of the notch sufllciently for engagement by said cam endsubsequently, and coacting devices in said housing and on said key shankIor preventing said shank from turning on said post.

3. A switch of the class described comprising a housing having a keyentrance opening therein, a fixed contact in the housing, a. pivotedcontact arm in said housing swingable in opposite directions to engageand disengage the fixed contact, respectively, a key piloting post insaid housing axially aligned with said opening and having a side notchtherein, a boss on one end of said arm adapted to be entered in saidnotch when said arm is swung to disengage said fixed contact, springmeans ior swinging said arm to disengage the same from the fixedcontact, akey having a tubular shank for insertion through said openingand sliding along said post forwardly, a beveled end on said shank forcamming engagement with said boss to cam the same out of the notch andswing said arm into engagement with the fixed contact when said shank isslid forwardly, said boss having a corner exposed out oi said notch torcamming engagement by said beveled end to initially earn the bossoutwardly of the notch suillciently for engagement by said cam endsubsequently, and coacting devices in said housing and on said key shankfor preventing said shank from turning on said post comprising a keyguide surrounding said post and having a grooved guideway therein. and arib on said shank for sliding in said groove.

PATRICK H. CHILDRESS.

